#include<iostream>
#include<stack>
using namespace std;
float obliczONP (string x)
{
	stack<float> q;
	float a,b;
	getline( cin, x);

	for(int i=0;i<x.length();i+=2)
	{

			if(x[i]>='0' && x[i]<='9')
				q.push(x[i]-48);
			else
			{
				b=q.top(); q.pop();
				a=q.top(); q.pop();

				if(x[i]=='+')
					q.push(a+b);
				else if (x[i]=='-')
					q.push(a-b);
				else if (x[i]=='*')
					q.push(a*b);
				else
					q.push(a/b);
			}
	}
	return q.top();
}
int main()
{
	int a;
	string x;
	cout<<"1.Oblicz ONP"<<endl;
	cin>>a;
	if(a==1)
		{
			cout<<"Podaj obliczenie"<<endl;
			getline (cin, x);
			cout<<obliczONP(x);
		}
}